cimom implementation. what is pegasus? pegasus is an open-source reference implementation of the...

CIMOM Implementation

What is Pegasus?

• Pegasus is an open-source reference implementation of the DMTF WBEM specifications

• Pegasus is a work project of the TOG Enterprise Management Forum

• Pegasus is a platform for building application management• Pegasus is a function-rich, production-quality open-source

implementation designed to be used in high volume server implementations.

Why Produce Pegasus?

• Demonstrate manageability concepts.

• Provide additional standards for WBEM

• Provide a working implementation of WBEM technologies

• Provide an effective modular implementation

• Support other Open Group manageability standards

• Base Platform for Open Group Application management Projects

• Help make WBEM real

Pegasus was Initiated in 2000 by the Open Group in collaboration with:

BMC SoftwareIBMTivoli Systems

Key Pegasus Objectives

Pegasus

Open Source

Portable

EfficientAnd

Lightweight

StandardsBased

Continuity

ModularAnd

ExtensibleProduction

Quality

Pegasus Working Group Philosophy

• Manageability not management– The Pegasus working group’s objective is not to manage systems but to make

them manageable by promoting a standard instrumentation environment

– The actual management of systems is left to systems management vendors

• No standards without implementation– The process of implementation provides a rigorous process for testing the

validity of standards

– Therefore all standards must be validated by implementation

Open Source

• Code and documentation freely available– Open Group and Source Forge

• MIT source license

• Open to contributions

• No commitment to Open Group to use code

Portable

• Designed for multi-platform, multi-OS, multi-compiler implementation

• Platforms ported today– UNIX (AIX, HPUX, Solaris, Tru-Unix)

– Linux

– Windows Platforms (NT, 2000, 9x)

– Compaq Himalaya (Tandem)

Efficient and Lightweight

• Core written in C++

• Designed for execution efficiency

• Designed to be production-quality solution

Standards Based

• Based on DMTF CIM and CIM-XML specifications

• Open Group is active partner in DMTF

• Growth through participation in specification growth

• Commitment to continue DMTF compliance

Modular and Extensible

• Minimize core object broker.

• Maximize extensibility through plug-in components

• Component types– Providers

– Provider interfaces

– Clients

– Repositories (additional repository handlers)

– Manageability service extensions

– Protocol Adapters

– Modules (extend and modify core functions)

Modularity is key to doing parallel development and allowto extensibility

Project for Continued Development

• WBEM will continue to develop functionality and standards

• Open Group will develop application management partly around Pegasus

• Pegasus Development will continue beyond current versions– Integrate contributions

– Add basic new functionality

– Etc.

The Open Group

• Enterprise Management Forum– Projects include:

• Pegasus

• Ex-SNIA Java Based open-source Implementation

• Application Management APIs

– ARM

– AIC• Software Licensing Standards

• QoS Task Force– User/Supplier interaction forum to advance QoS and Service Level

Standards

– Working with DMTF, IETF, TMN

2. The Pegasus Environment

Pegasus Architecture

ConsumersConsumersConsumersConsumers

ClientsClients

CIM ServerCIM Server


ProvidersProviders

CIM/HTTPInteroperable*

Interoperable* CIM/HTTP In-Process

ServicesServices

StandardInterfaces

MOF

Compiler

MOF

Compiler

CIMOM Capabilities

• Respond to Operations defined in “CIM Operations” spec.– Create, Modify, Delete operations on

• Class, Instance, Property, Qualifier

• Handle Provider Registration• Forward Requests to Providers, repositories, etc.• Read/Write access to Management Information

– Maintain Class/Instance Information

• Traversal of Associations• Use of WBEM Query Language• Syntax/Semantic checking (with Qualifiers)• Available Implementations

– Microsoft (in Windows2000), Sun WBEM SDK, SNIA, Open Group Pegasus, …

Key Interoperability Interfaces

CIM Object Manager

CIM Object Manager

CIM ProvidersCIM Providers

ApplicationApplication

Manageability to Manager•Multiple management systems•Common open manageability

Object Manager / Providers• Multiple Providers•Encourage common providers

Management System

Management System

EnterpriseManagement

Console

EnterpriseManagement

Console

ApplicationApplicationApplicationApplication

ApplicationApplication

Provider / Resource Interface•Protect Applications•Make application management easy

The CIM Operations


ClientsClients

CIM Object MgrCIM Object Mgr


ProvidersProviders



ServicesServices

StandardInterfaces

Repository

CIMOperations

CIMOperations

Repository

Operations Routing

• Class Operations– Routed to the Class Repository

• Instance Operations– To Provider if Provider Qualifier exists

– To Instance repository if no Provider

• Instance routing at Class Level Today– Issues – Routing at instance level

The CIM Indications


ClientsClients

CIM Object MgrCIM Object Mgr


ProvidersProviders



ServicesServices

StandardInterfaces

RepositoryRepository

IndicatorsIndicators

Indication

HandlersSNMP, cim-

xml, etc.

SNMP, cim-xml, etc.

Modularity and Extensibility

• Providers– Grow with DMTF provider concepts

• Provider Interfaces• Protocol Adapters (connectors)

– Client - Xml-cim today (Soap, etc. in future)– Provider, service, repository, etc.

• Modules– Modularize core so it can be extended and modified through attachable modules

• Manageability Service Extensions– Think super providers

Building A Modular Manageability Environment

CoreObjectBroker

CoreObjectBroker

XML-CIM

ModuleModule

ModuleModule

ModuleModule

ModuleModule

ConnectorConnector

ProviderProvider

ConnectorConnector

ProviderProvider

ConnectorConnector

CIM ClientCIM ClientConnectorConnector

. . .

Resources Resources Resources

ServiceExtension

ServiceExtensionService

Extension


Extension


Extension

ServiceExtension


Undefined

CIM ClientCIM ClientCIM ClientCIM Client



ServiceExtension


Extension


Extension


Extension

ServiceExtension

ManagementSystem Connector


Pegasus Manageability Environment

CIM Object Broker•Provider Registration •Service Registration•Request Routing •Securiy

CIM Object Broker•Provider Registration •Service Registration•Request Routing •Securiy

Consumers

Providers

AICProvider

AICProvider

Apps OS Etc.

ARMProvider

ARMProvider

Resource

Providers

Broker

Consumers Gateways Apps

XML/CIMConnector

XML/CIMConnector



ApplicationConsumer

ApplicationConsumer

ClassRepository

ClassRepository

Services core*** additional

InterfaceFor Spec

CIMOMManagement

System

. . .SNMPProvider

SNMPProvider

ManagementSystem

ApplicationConsumer

ApplicationConsumer

ApplicationConsumer

ApplicationConsumer

InstanceRepository

InstanceRepository

Provider Interoperability

• In the classical architecture, interoperability is only supported between the client and server.

• In addition, the Pegasus architecture aims to support provider/server interoperability.

• Goal– Write a provider once and run it under any CIM server implementation.

• Provider/Server Interoperability:– Participating in efforts to standardize the Provider/Server protocol.– Proposing provider API standards.– Writing adapters enabling Pegasus providers to run under other CIM servers.– Adapters enabling other providers to run under Pegasus

Important Provider Interfaces

• SUN WBEM Provider Interface– Java based

– Classes, etc. “similar” to Pegasus

• C Provider Interface– Sun has a specification here.

• We will support multiple provider interfaces and language bindings.

In-Process and Out-of-process Providers

• Today Pegasus based on shared Library Providers• Extend to

– Internal Providers– IPC based Providers– Providers in Remotes systems

• Objectives:– Write Provider once and compile/link for different environments

• Technique– Use connectors as basis for provider/CIMOM communication

• Issues– Security, discovery

Manageability Service Extensions

• Super Providers

• Access to the Core Broker

• Examples– Indication Subscription service.

– Class repository service.

– Instance repository service.

Connectors (Protocol Adapters)

• Functions– Adapt to different protocols

• Characteristics– Protocol– Encoding– Security– Discovery

• Examples– Xml-CIM– Local Protocols– Soap– WMI– Corba environment interface

Pegasus CorePegasus Core

Xml-cimConnector

Xml-cimConnector

PegasusProvider

PegasusProvider

ConnectorConnector

RemoteProvider

Xml-cimClient

Xml-cimClient

SoapConnector

SoapConnector

SoapClient

SoapClient

CorbaConnector

CorbaConnector

ExternalCorba

Environment

ServiceExtension


Extension


Extension


Extension

ServiceExtension


Pegasus Interfaces

• Common Interface base for– Clients, providers, services,

connectors

• Based on CIM Operations over HTTP

• Additional functions for each interface

• Interfaces separated from implementation

CoreObjectBroker

CoreObjectBroker

ProviderProvider

ConnectorConnector

CIM ClientCIM ClientConnectorConnector

3. The Pegasus Software Architecture

Major Components

Client

CIM Server Repository

ClientCIMClients

ClientClientCIMProviders

Topics

• Communication.

• Representation of CIM Elements.

• The Client Interface.

• The CIM Object Manager.

• The Provider Interface.

• The Repository Interface.

Pathways of Communication

Client

CIM Server CIMRepository

ClientCIM Clients

ClientClientCIM Providers

Component Location

• A component may be located in one of three places with respect to the CIM Server.– In-process.

– Local out-of-process (on the same machine).

– Remote out-of-process (on another machine).

• For example, a provider may be in-process, local, or remote.

Component Location in Pegasus Today

In-Process Local Remote

Client X

Provider X

Repository X

Possible Communication Mechanisms

• Components could potentially communicate with the CIM Server using the following mechanisms:– CIM/HTTP (remote).

– Proprietary TCP-based protocol (remote).

– Direct call (in process).

– Shared memory (local).

– Named pipes (local).

Communication Mechanisms in Pegasus

In-Process Local Remote

Client CIM/HTTP

Provider Direct Call

Repository Direct Call

Client Communication

• Uses CIM/HTTP as sole protocol.

• Asynchronous socket I/O.

• An efficient XML parser.

• Fast enough to eliminate the need for a proprietary protocol.

An Efficient XML Parser

• No memory heap usage during parsing.

• Modifies message in place to avoid copying.

• Non-validating parser (“loose validation”).

HTTP Implementation

• Uses asynchronous socket I/O in conjunction with message queues to achieve optimal throughput.

• Provides entry points to adding web server capabilities such as putting and getting of documents (to support remote upgrade and deployment later on).

Proposals

• Support out-of-process providers (local and remote).

• Support out-of-process repositories (local and remote).

• Location independent provider development.

Representation of CIM Elements

Representing CIM Elements in Pegasus with C++

CIM Data Types in C++

• Uint8• Sint8• Uint16• Sint16• Uint32• Sint32• Uint64• Sint64• Real32• Real64

• Boolean• Char16• String• CIMDateTime• CIMReference

CIM Values in C++

• CIM values (property, parameter, and qualifier values) are represented using the CIMValue class. This class:– Encapsulates a union of all CIM data types.

– Has a type member indicating the type currently being represented.

– Provides access/modifier methods overloaded for each CIM data type.

CIM Elements in C++

• CIMClass• CIMInstance• CIMProperty• CIMMethod• CIMParameter• CIMQualifierDecl• CIMQualifier

Class Declaration Example (Part 1)• Consider the following MOF class declaration:

class Alarm{ [key] uint64 id; string message = “none”;};

• This class is defined in C++ as follows:CIMClass alarmClass(“Alarm”);CIMProperty id(“id”, Uint32(0));id.addQualifier(CIMQualifier(“key”, true)); CIMProperty message(“message”, “none”);alarmClass.addProperty(id);alarmClass.addProperty(message);

• Or more succinctly like this:CIMClass alarmClass(“Alarm”);alarmClass .addProperty(CIMProperty(“id”, Uint32(0)) .addQualifier(CIMQualifier(“key”, true))) .addProperty(CIMProperty(“message”, “none”));

Property Iteration Example:

• The properties of a class may be iterated like this:CIMClass c;

…

for (Uint32 i = 0, n = c.getPropertyCount();

i < n; i++)

{

CIMProperty p = c.getProperty(i);

}

The Client Interface

Client


ClientCIMClients


The Client Interface

• A C++ interface for interacting with the Pegasus Server (or any CIM Server).

• Uses CIM/HTTP to communicate.

• Provides a method for each CIM operation defined in the “CIM Operations over HTTP, V1.0” specification.

The CIM Operations

• GetClass

• GetInstance

• DeleteClass

• DeleteInstance

• CreateClass

• CreateInstance

• ModifyClass

• ModifyInstance

• EnumerateClasses

• EnumerateClassNames

• EnumerateInstances

• EnumerateInstanceNames

• ExecQuery

• Associators

• AssociatorNames

• References

• ReferenceNames

• GetProperty

• SetProperty

• GetQualifier

• SetQualifier

• InvokeMethod

CIM Operation Example

virtual CIMInstance getInstance( const String& nameSpace, const CIMReference& instanceName, Boolean localOnly = true, Boolean includeQualifiers = false, Boolean includeClassOrigin = false, const Array<String>& propertyList =

NULL_PROPERTY_LIST);

<instance> GetInstance ( [IN] <instanceName> InstanceName, [IN,OPTIONAL] boolean LocalOnly = true, [IN,OPTIONAL] boolean IncludeQualifiers = false, [IN,OPTIONAL] boolean IncludeClassOrigin = false, [IN,OPTIONAL,NULL] string PropertyList [] = NULL )

CIM Operations

Specification

PegasusClass

Method

Client Connection Example

• A client connects to the CIM Server on the host called “saturn” at port 5988 like this:Selector selector;

CIMClient client(&selector);

client.connect(“saturn:5988”);

GetClass Example

• A client gets a class like this:CIMClass alarmClass =

client.getClass(“root/cimv2”, “Alarm”);

Client Proposals

• Asynchronous Interface APIs

• Interface independent of local/remote client

The Pegasus CIMOM

Client


ClientCIMClients


Request Lifecycle

Channel

Protocol

Encodings

Dispatcher

ProvidersProvidersProviders

Repository

1. Receive TCP Message

2. Process HTTP Request

3. Decode from XML

4. Dispatch Request

Incoming Request

Channel

Protocol

Encodings

Aggregator

8. Transmit TCP Message

7. Form HTTP Response

6. Encode to XML

5. Aggregate Results

Outgoing Response

CIMOM Modules

• Channel - Implements transport mechanism (e.g., TCP).• Protocol - Implement application protocol (e.g., HTTP).• Encodings - Implements encoding and decoding of messages

(e.g., CIM-XML).• Dispatcher - Dispatches messages to provider(s)/repository.• Repository - Implements CIM Repository.• Aggregator - Aggregates results.

Module Concept

• The internal CIMOM architecture is being refined into a set of modules.

• Each module handles part of the request lifecycle.

• Alternative implementations may be provided for each module type.

• New module implementations can be used to modify or refine the behavior of the CIMOM and to facilitate porting.

Module Implementations

• Channel - provide a named-pipe implementation.• Protocol - provide a proprietary binary protocol.• Encodings - provide a binary encoding scheme.• Repository - provide a relational-based implementation.• Traffic Encryption - SSL implementation.• Authentication – Challenge and response

Queued Operation Model

• Internal representation of operations/Indications is messages

• Major components are queue driven

• Mapped to direct interfaces (ex. getClass) at provider manager.

• Message manager controls flows, priorities, etc.

• Advantages– Efficiency

– Threading

– Extensible interfaces

– Flow Control

Module Definition and Loading

• Modules implement one of the module interfaces (e.g., Repository).

• Modules are configured as dynamic libraries.

• Modules listed in modules file.

• Modules loaded by CIMOM on startup.

Provider Mgr Subsystem

CIM XML Comm Module

CIM Operations Processing subsystem

Services Subsystem

PegasusMsgDispatcher

IndicationHandlerManager

CIM-XMLIndication

handler

Repository

ProviderManager

provider

CIM Control Services•Start/Stop Function•Provider registration Function•User/Auth. Function•jj•Jj•__Namespace

SubscriptionService and

Indication Processor

IndicationImport

providerprovider

Client Interface (cim-xml today)

Acceptor

HttpDelegator

Authentication

XMLDecoder

XMLEncoder

Authorization

OperationsRequest

Processor

OperationsResponseProcessor

Responsegenerator

Formal ProviderInterface

IndicationConsumerManager

IndicationConsumerManager

CIM ExportRequest Processor

CIM ExportRequest Decoder

ExportIndication

Pegasus Module Organization

LocalDestination

SNMPIndication

handler

Httpxxx

xxx

The Provider Interface

Client


ClientCIMClients


Provider Proposals

• Interoperability with SUN Wbem providers proposal

• We are extending other interoperability ideas

PegasusCIMOM

PegasusCIMOM

SUN WBEMCIMOM

SUN WBEMCIMOM

MicrosoftCIMOM

MicrosoftCIMOM

PegasusProviders

PegasusProviders

SUN WBEMProviders

SUN WBEMProviders

Microsoft WMIProviders

Microsoft WMIProviders

The Repository Interface

Client


ClientCIMClients


The Repository Interface

• Defines the interface to manipulating the CIM repository.

• Alternative implementations of this interface may be provided.

• Pegasus provides a simple default implementation.

Default Repository Implementation

• Each CIM Class object is stored in its own file.• Instance objects stored in single file for each class• CIM objects are encoded as XML in files.• Namespaces are represented using file system directories.• Single reader/writer at a time.• Example: the class X (subclass of Y) which resides in the

root/cimv2 namespace would be stored in this file:

<repository_root>/root#cimv20/classes/X.Y

Default Repository Limitations

• Adequate for classes and qualifiers (which tend to be few).

• Okay for a few hundred instances.

• Not intended to scale to thousands of instances (uses a lot of disk space due to internal fragmentation).

• Good for scenario in which a few instances come from the repository and many instances come from providers.

Proposed Repository Implementation

• A new repository implementation is under consideration to improve scalability:– Encode objects in binary on disk (rather than XML). This will reduce size

by three to one.

– Combine like objects into a single file rather than separate files (this will reduce internal fragmentation).

– Provide a fast indexing scheme for keys (disk hashing or B+-Trees). This will improve lookup time.

Alternative Repository Modules

• Repository modules may be developed to achieve a highly scalable repository. Possibilities include:– Basing repository on a relational database.

– Basing repository on Unix DB.

– Making the repository remote.

– Improving space utilization of existing implementation by storing objects in binary format (rather than as XML).

cimom implementation. what is pegasus? pegasus is an open-source reference implementation of the...

Documents

group philosophymanageability

availableopen group

standardsopen group

dmtf cim

managementthe pegasus

dmtf compliancemodular

additional standards

cim operations spec